Read the given statements and select the correct option.
(i)Synaptic cleft of neurons secreates adrenaline.
(ii)Myelinated nerve fibres are enveloped with Schwann cells, which form a myelin sheath around the axon.
(iii)Non-myelinated nerve fibre is enclosed by a Schwann cell that does not form a myelin sheath.
(iv)Spinal and cranial nerves are made of non-myelinated nerve fibres.

Options

A. a, b are correct , but c and d are incorrect
B. a, b and c are correct , but d is incorrect
C. c , d are correct, but a and b are incorrect
D. b, c are correct but a and d are incorrect

Answer

D